There are 30 terms in the geometric sequence.
The first term is 1
The common ratio is -4/5
Using this, we get:
[tex]S_n = \frac{a(1- r^{n}}{1 - r}[/tex]
[tex]S_30 = \frac{(1 - (-\frac{4}{5})^{30}}{1 + \frac{4}{5}}[/tex]
Plugging this into the calculator gives you 0.554867811..., which is approximately 0.55.
